This invention relates to a friction disk used in clutch and brake assemblies in which the friction disk and a reaction plate are in relative rotation. The plate and disk are normally spaced and are brought into frictional engagement for the purpose of braking or transmission of torque.
Historically, friction disks have been made from a flat circular steel backing plate, with a circular or annular flat layer of friction material being secured to one or both sides of the backing plate or core. A splined central opening may be provided in the backing plate for mounting on a shaft, or the outer perimeter may be splined for engagement with a mating matching spline. These assemblies are either air cooled or run in a bath of liquid.
In recent times, particularly in the automotive industry, there has been a strong demand to reduce costs, and suppliers to this industry have been seeking ways to reduce the costs of various components without sacrifice to performance and service life.
In the production of friction disks, the steel backing plate for the friction material is blanked from a flat sheet of steel using a circular die, and regardless of the blanking method used, this operation results in the generation of scrap between blanked areas, which significantly contributes to the overall cost of production. The layer of friction material is often cut from blanks, usually in the form of flat rings or disks, for application to the backing plate. The blanking of the friction ring results in additional scrap because of the material between blanked areas.